Self-mailer forms (e.g., for check stock) are in general well-known. With such forms persons may print (or type) a message then fold and seal the form into a mail piece suitable for mailing. These mailers have been produced from continuous webs of stock and are intended for use on the high speed printers of main frame computers. For example, custom self-mailers represent an important piece of business stationary, which may include laser bond stocks designed to fold and seal in a specific configuration.
In the design of self-mailers, a pressure sensitive adhesive can be coated in strips which are placed to contact each other during sealing. Prior to the sealing operation, the self-mailers can be printed on printing machines, where a toner image can be fixed or fused upon a support (e.g., a plain paper sheet) using a fuser roll. In order to ensure and maintain good release properties of the fuser roll, it has become customary to apply release agents/fuser oils to the fuser roll during the fusing operation. Typically, these release agents/fuser oils are applied as thin films of nonfunctional or functional silicone oils to prevent toner offset.
A variety of silicone oils have been used in the prior art. For example, U.S. Pat. No. 4,029,827 discloses the use of polyorganosiloxanes having mercapto functionality as release agents. U.S. Pat. No. 4,101,686 and U.S. Pat. No. 4,185,140 disclose polymeric release agents having functional groups such as carboxy, hydroxy, epoxy, amino, isocyanate, thioether, or mercapto groups. U.S. Pat. No. 5,157,445 discloses toner release oil having a functional organopolysiloxane. U.S. Pat. No. 5,512,409 teaches a method of fusing thermoplastic resin toner images to a substrate using amino functional silicone oil over a hydrofluoroelastomer fuser member. U.S. Pat. No. 5,516,361 teaches a fusing member having a thermally stable hydrofluoroelastomer surface and having a polyorgano T-type amino functional oil release agents. The oil has predominantly monoamino functionality per active molecule to interact with the hydrofluoroelastomer surface. U.S. Pat. No. 5,531,813 discloses a polyorgano amino functional oil release agent having at least 85% monoamino functionality per active molecule to interact with the thermally stable hydrofluoroelastomer surface of the fuser member. U.S. Pat. No. 5,716,747 discloses the use of fluorine-containing silicone oils for use on fixing rollers with outermost layers of ethylene tetrafluoride perfluoro alkoxyethylene copolymer, polytetrafluoroethylene and polyfluoroethylenepropylene copolymer. U.S. Pat. No. 5,747,212 discloses an amino functional oil. U.S. Pat. No. 6,183,929 discloses a release agent comprising an organosiloxane polymer containing amino-substituted or mercapto-substituted organosiloxane polymers and a nonfunctional organosiloxane polymer. U.S. Pat. No. 4,029,827 describes the use of polymeric release agents having functional groups, which interact with a fuser member to form a thermally stable, renewable self-cleaning layer having good release properties for electroscopic thermoplastic resin toners.
Problems arise, however, due to the formation of a thin film of release agents/fuser oils on the pressure sensitive strips during the fusing operation, which may contaminate the strips and lead to a sealing failure thereafter. This problem is familiar to the industry and some solutions are disclosed in the prior art, such as in U.S. Pat. No. 4,918,128, U.S. Pat. No. 5,427,851, U.S. Pat. No. 6,383,653, and U.S. Pat. No. 6,602,944. These conventional solutions include the development of fuser roll materials and silicone release oils, as well as the demands of color and higher speed printing. The conventional solutions, however, continue to make it difficult for pressure seal mailers to perform adequately after contamination by fuser oils. For example, this is particularly the case for digital color production printers employing functionalized polydimethylsiloxane (PDMS) release oils where the functional group is mercapto or amino. Specifically, there are three basic problems associated with fuser oils. Firstly, the cohesive material softens in the fusing nip offsetting and contaminating the printer; secondly, the release oil interferes with the ability to form a cohesive bond; thirdly, the continued presence of the release oil on the cohesive results in blocking on stacked sheets.
Thus, there is a need to overcome these and other problems of the prior art and to provide a pressure-seal cohesive for use in mailers type business forms even when functionalized PDMS oils are used for fusing operation.